Detection of Winding Deformation In Power Transformers

This paper discusses the transfer function method as a tool for detection of winding deformations in power transformers. A series of transfer function measurements on selected transformer rating were carried out on the active part within the transformer and thereafter without bushings, oil and tank. using a network analyzer. The new transfer functions were measured after the application of the vertical and radial deformations to the windings and after the replacement of the active part in the tank and oil refilled. For this particular transformer construction, it is evident that only vertical deformations can be detected by the transfer function method.